[Cluster-devel] disallowed in cluster3

[David Teigland <teigland@redhat.com>]

On Thu, Aug 06, 2009 at 08:08:37AM +0100, Christine Caulfield wrote:
> On 05/08/09 17:52, David Teigland wrote:
> >When rewriting daemons for cluster3 to remove groupd, I wrote them to not 
> >need
> >or use the disallowed-nodes feature from cman for handling remerging of
> >cluster partitions.  In compat mode, however, (the cluster2 code) they 
> >would
> >still depend on that cman feature, which is why it still exists in cluster3
> >cman.
> >
> >I've found, though, that when we do have a partition remerge, cman's
> >disallowed feature gets in the way of the daemons trying to handle it
> >themselves (which I'm testing, it doesn't seem quite right in all
> >partitioning/merging cases yet.)
> >
> >So, I think what we need is for cluster3 cman to turn off the disallowed
> >feature unless the cluster is in compat mode, i.e.<group 
> >groupd_compat="1"/>
> >exists.
> 
> 
> Thanks, I've been looking for an excuse to add code to cluster3 to 
> disable that mode ;-)
> 
> I'm not happy with cman reading groupd tags out of cluster.conf though. 
> The alternatives are to have an extra tag for cman, but that risks users 
> only setting one or the other and causing havoc. So how about a higher 
> level <cluster compat="x"> flag ?

Yeah, the group/groupd_compat is a little odd in that way... I have all my
daemons checking for that one tag.  cluster compat wouldn't be bad, or instead
of a cluster attribute it could be a more generic element -- that would just
mean changing <group groupd_compat="x"/> into <compat version="x"/> or
something like that.

With the release out, I think it's too late to remove group/groupd_compat, but
we can add something new that supersedes it.